1. Field of the Invention
The present invention relates generally to the field of computer networks, and specifically, to network forwarding using Dynamic Host Configuration Protocol (DHCP) tagging.
2. Background Information
The Dynamic Host Configuration Protocol (DHCP), published by the Internet Engineering Task Force (IETF) as Request for Comment (RFC) 2131 in March 1997 [hereinafter referred to as xe2x80x9cthe DHCP specificationxe2x80x9d], was created to facilitate automatic assignment/leasing of Internet Protocol (IP) addresses to clients when such clients log on to TCP/IP networks. The contents of the DHCP specification are fully incorporated herein by reference. A DHCP server centrally manages the assignment and reassignment of unused IP addresses.
In a subscriber network system such as a cable modem system, IP addresses are assigned by the DHCP server to subscribers via a shared physical medium. The cable modems used by subscribers also include a media access control (MAC) address. To send packets to a subscriber from a web server, the IP address of the subscriber must be translated into a MAC address. This is typically done using an Address Resolution Protocol (ARP), as defined in request for comment (RFC) 826, entitled xe2x80x9cAn Ethernet Address Resolution Protocolxe2x80x9d, Published in November 1982, where an ARP request is broadcasted for the unknown address. However, ARP requests introduce the possibility of spoofing (hacking).
The present invention comprises a method for a device in a system including a server and one or more client computers. In one embodiment, the method includes tagging one or more messages from a client computer to the server with a media access control (MAC) address of a cable modem that is attached to the client computer for storing the MAC address as part of a lease record in the server. The method further includes receiving a request for the MAC address of the cable modem based on the Internet protocol (IP) address of the client computer from a remote device for transmitting packets to the client computer, obtaining the MAC address of the cable modem corresponding to the IP address of the client computer from the server, and transmitting the MAC address to the remote device.
Other embodiments are described and claimed herein.